#include "NBody.hpp"

/////////////////////////////////// NBody::setupCLProgram() Func \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
//
// Build CL kernel program executable.
//
/////////////////////////////////// NBody::setupCLProgram() Func \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

int NBody::setupCLProgram()
{
	cl_int   status;

	/* create a CL program using the kernel source */
	char *program_source = load_program_source(kernelFileName);
	size_t sourceSize[] = { strlen(program_source) };
	
    program = clCreateProgramWithSource(
        context,
        1,
        (const char**)&program_source,
        sourceSize,
        &status);
  
	if (status != CL_SUCCESS){
		std::cout << "clCreateProgramWithSource failed." << std::endl;
		return 1;
	}

	/* create a cl program executable for all the devices specified */
    status = clBuildProgram(
                 program,
                 1,
                 &devices[0],
                 NULL,
                 NULL,
                 NULL);
    
	if(status != CL_SUCCESS)
    {
        if(status == CL_BUILD_PROGRAM_FAILURE)
        {
            cl_int logStatus;
            char * buildLog = NULL;
            size_t buildLogSize = 0;
            logStatus = clGetProgramBuildInfo (program, 
                                            devices[0], 
                                            CL_PROGRAM_BUILD_LOG, 
                                            buildLogSize, 
                                            buildLog, 
                                            &buildLogSize);
			if (logStatus != CL_SUCCESS){
				std::cout << "clGetProgramBuildInfo failed." << std::endl;
				return 1;
			}
           
            buildLog = (char*)malloc(buildLogSize);
            if(buildLog == NULL)
            {
                std::cout << "Failed to allocate host memory. (buildLog)" << std::endl;
                return 1;
            }
            memset(buildLog, 0, buildLogSize);

            logStatus = clGetProgramBuildInfo (program, 
                                            devices[0], 
                                            CL_PROGRAM_BUILD_LOG, 
                                            buildLogSize, 
                                            buildLog, 
                                            NULL);
			if (logStatus != CL_SUCCESS){
				std::cout << "clGetProgramBuildInfo failed." << std::endl;
				free(buildLog);
				return 1;
			}
       

            std::cout << " \n\t\t\tBUILD LOG\n";
            std::cout << " ************************************************\n";
            std::cout << buildLog << std::endl;
            std::cout << " ************************************************\n";
            free(buildLog);
        }
        
		if(status != CL_SUCCESS)
        {
            std::cout << "clBuildProgram failed." << std::endl;
            return 1;
        }
    }
}

/////////////////////////////////// NBody::load_program_source Func \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
//
// Loads the kernel code form a .cl file type and returns the source code as a char*
//
/////////////////////////////////// NBody::load_program_source Func \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

char* NBody::load_program_source(const char *filename)
{ 
	FILE *fh; 
	char *source; 
	int size;
	
	fh = fopen(filename, "r");
	if (fh == NULL){
		std::cout << "Reading the source cod for kernel failed." << std::endl;
		exit(1); 
	}
	
	fseek (fh, 0, SEEK_END);
    size = ftell (fh);
	rewind(fh);

	source = (char *) malloc(size+1);

	int result = fread(source, 1, size, fh);
	/*if (result != size){
		std::cout << "Reading the source cod for kernel failed." << std::endl;
		exit(1); 
	}*/
	source[result] = '\0';
	
	fclose(fh);
		
	return source; 
}